How to Take Magnesium citrate: Side Effects, Dosage
Magnesium citrate dosing instructions per OTC labeling, side effects, and when to consult a healthcare provider.
Not medical advice. Speak with a healthcare professional before using any medication.
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Updated Feb, 15
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Information sourced from FDA-approved prescribing information and peer-reviewed medical references.
How to Take Magnesium citrate
How to Take Magnesium Citrate
Per OTC labeling, magnesium citrate is typically used as a single dose for occasional constipation relief. Follow the directions on the product label.
- Per OTC labeling, adults: most liquid products are taken as 150–300 mL (5–10 oz) one time, as directed on the label.
- Per OTC labeling, children 6–11 years: 75–150 mL (2.5–5 oz) once, as directed. Consult a clinician before use.
- Per OTC labeling, children 2–5 years: 30–75 mL (1–2.5 oz) once, as directed. Not for children under 2 unless directed by a clinician.
- Per OTC labeling, hydration: drink at least 1 full glass of water after the dose, and continue sipping fluids throughout the day.
- Per OTC labeling, timing: the product typically works within 30 minutes to 6 hours. Choose a time when access to a bathroom is convenient.
- Per OTC labeling, other medicines: take other oral medications 2–3 hours before or after magnesium citrate so they absorb properly.
Warnings Before Taking Magnesium Citrate
- Per OTC labeling: avoid if you have kidney disease or impaired ability to clear magnesium.
- Per OTC labeling: do not use with severe stomach pain, nausea, or vomiting unless directed by a clinician.
- Per OTC labeling: check with your doctor if you follow a low-sodium or fluid-restricted plan.
- Per OTC labeling: ask before using if you take medications that affect electrolytes.
- Per OTC labeling: if pregnant or breastfeeding, confirm use with your clinician.
Magnesium citrate Side Effects
Common
Mild
Diarrhea
Per OTC labeling, magnesium citrate can draw water into the intestine, leading to loose or watery stools. This is the expected laxative effect.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
4–12 hours
Common
Mild
Abdominal Cramping
Per OTC labeling, some people feel cramping or mild abdominal discomfort as the bowels become more active.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
1–3 hours
Occasional
Mild
Nausea
Per OTC labeling, nausea may occur as the stomach reacts to the increase in intestinal fluid movement.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
30–90 minutes
Occasional
Mild
Bloating or Gas
Per OTC labeling, temporary bloating or increased gas may occur as the intestines shift fluid.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
1–4 hours
Rare
Moderate
Electrolyte Imbalance
Per OTC labeling, frequent watery stools can occasionally lower electrolytes such as sodium or potassium, causing weakness or lightheadedness, especially with repeated doses.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
a few hours
Occasional
Moderate
Dehydration
Per OTC labeling, increased fluid loss through the bowels can lead to thirst or mild dizziness. Drink clear fluids as directed to prevent dehydration.
Per OTC Drug Facts labeling. If symptoms persist or worsen, stop use and consult a healthcare provider.
Normally lasts for:
a few hours to 1 day
Contact Us for a Personalized Care Plan
Have questions about compounding? Contact Voshell's Pharmacy — we prepare patient-specific medications pursuant to valid prescriptions from your licensed prescriber.
What If You Forgot to Take Magnesium citrate
What If You Forgot to Take Magnesium Citrate?
Per OTC labeling, if you miss a dose, take it as soon as you remember, as long as it is not too close to the next scheduled dose. If it is almost time for the next dose, skip the missed dose and return to your usual schedule.
Do not double up; taking extra doses will not improve effectiveness and may cause excessive bowel movements.
Per OTC labeling, if you use magnesium citrate only as a one-time laxative, take it when you remember as long as the need persists.
What If You Took Too Much Magnesium citrate
What If You Took Too Much Magnesium Citrate (Accidentally)?
Call Poison Control at 1-800-222-1222 immediately for guidance on next steps.
Per OTC labeling, magnesium citrate overdose may cause severe diarrhea, electrolyte imbalances (particularly in people with kidney impairment), muscle weakness, irregular heartbeat, or low blood pressure. If symptoms are severe, call 911 or go to the nearest emergency room.
How Much Does Magnesium citrate Cost
Cost of Magnesium Citrate With Insurance
Magnesium citrate is an over-the-counter product. Most standard insurance plans do not cover OTC medications. FSA/HSA funds may be applicable for eligible products; verify eligibility with your plan. Pricing information is not a guarantee of cost; contact your pharmacy for current pricing.
How Much Does Magnesium citrate Cost without Insurance
Magnesium Citrate Cost Without Insurance
Magnesium citrate is an over-the-counter product available at most pharmacies and retailers. Prices vary by brand, formulation, and store. Store-brand generics are generally available at lower cost than branded products. Pricing information is not a guarantee of cost; contact your pharmacy for current pricing.
Resources:
https://medlineplus.gov/druginfo/meds/a601074.html
https://www.drugs.com/mtm/magnesium-citrate.html
https://www.mayoclinic.org/drugs-supplements/magnesium-citrate-oral-route/description/drg-20074731
https://www.nhs.uk/medicines/magnesium/
https://pubchem.ncbi.nlm.nih.gov/compound/Magnesium-citrate
